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deep - definition and synonyms

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adjective     deep pronunciation in American English
Word Forms
  1. 1
    going a long way down from the top or the surface

    The river is pretty deep here.

    an area of high hills and deep valleys

    1. a.
      used for saying or asking the distance from the top or surface of something

      How deep is the snow?

      2 meters deep/6 feet deep etc.:

      The pond needs to be at least ten feet deep.

    2. b.
      going a long way into something

      He had a deep cut on his forehead.

      deep inside:

      By this time we were deep inside enemy territory.

      deep in:

      a small cabin deep in the woods

  2. 2
    going a long way back from the front of something

    The shelves need to be a little deeper than that.

  3. 3
    a deep feeling or emotion is very strong

    I do feel a very deep sympathy for them all.

    a feeling of deep gratitude

  4. 4
    a deep sound is low

    I recognized George’s deep voice on the other end of the phone.

    a deep roaring sound

  5. 6
    a deep sleep is one that you do not wake up easily from

    She fell into a deep sleep.

  6. 7
    breathing a lot of air into or out of your body

    Take a few deep breaths to calm yourself down.

    He looked at Rosie and gave a deep sigh.

  7. 8
    someone who is deep has very serious thoughts, ideas, or feelings
    1. a.
      something that is deep involves very serious thoughts, ideas, or feelings

      We had a very deep discussion about love and death.

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deep learning

a form of machine learning which incorporates the use of neural networks

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